The overall goals of this project are to investigate the kinetics of microbial degradation of pollutant mixtures and to apply this information toward the development of a novel bioreactor capable of removing a mixture of pollutants from water. Specifically, multiple substrate kinetics will be studies : benzene, phenol, and trichloroethylene consumption by Pseudomonas putida F1(and the inhibitory effects of chloroform) trichloroethylene and chloroform consumption by N. europaea benzene, phenol, trichloroethylene, and chloroform consumption by a mixed methanogenic culture Kinetic model parameters will be obtained by evaluating data from batch cultivations (yielding information on inhibition and high growth rate kinetics) and continuous cultivations (providing information on degradation kinetics at low growth rates). The case of trichloroethylene and phenol cometabolism by P. putida F1 will be examined in greater detail: in addition to the batch and steady-state continuous experiments, unsteady- state studies on both free and immobilized cells will be performed, and all of these data will be combined to develop an immobilized cell bioreactor capable of removing trichloroethylene (and phenol) from water. Currently, very little quantitative information is available on the rates and patterns of microbial degradation of multiple substrates. Many different types of interactions between substrates are possible, including cometabolism, inhibition, or even neutrality. Knowledge of these interactions and their kinetics is vital, not only for the design of bioreactors that can be used to remediate contaminated water but also for the prediction of the fate of pollutants in the environment, which is vital for the assessment of ecological and human health risks.